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31.
Elysia Poggi Davis Laura M. Glynn Feizal Waffarn Curt A. Sandman 《Journal of child psychology and psychiatry, and allied disciplines》2011,52(2):119-129
Objective: Prenatal exposure to inappropriate levels of glucocorticoids (GCs) and maternal stress are putative mechanisms for the fetal programming of later health outcomes. The current investigation examined the influence of prenatal maternal cortisol and maternal psychosocial stress on infant physiological and behavioral responses to stress. Methods: The study sample comprised 116 women and their full term infants. Maternal plasma cortisol and report of stress, anxiety and depression were assessed at 15, 19, 25, 31 and 36 + weeks’ gestational age. Infant cortisol and behavioral responses to the painful stress of a heel‐stick blood draw were evaluated at 24 hours after birth. The association between prenatal maternal measures and infant cortisol and behavioral stress responses was examined using hierarchical linear growth curve modeling. Results: A larger infant cortisol response to the heel‐stick procedure was associated with exposure to elevated concentrations of maternal cortisol during the late second and third trimesters. Additionally, a slower rate of behavioral recovery from the painful stress of a heel‐stick blood draw was predicted by elevated levels of maternal cortisol early in pregnancy as well as prenatal maternal psychosocial stress throughout gestation. These associations could not be explained by mode of delivery, prenatal medical history, socioeconomic status or child race, sex or birth order. Conclusions: These data suggest that exposure to maternal cortisol and psychosocial stress exerts programming influences on the developing fetus with consequences for infant stress regulation. 相似文献
32.
KI Wheeler GM Schmölzer CJ Morley PG Davis 《Acta paediatrica (Oslo, Norway : 1992)》2011,100(1):67-70
Background: Ventilator frequency is one of the determinants of tidal volume delivery during high‐frequency ventilation. Clinicians increasingly use data on ventilator displays to inform their decisions. Aim: To measure the frequencies delivered by the Dräger Babylog 8000plus ventilator when used in high‐frequency mode. Methods: Ventilator waveforms using a test lung were recorded at the full range of settings 5–20 Hz using Spectra software at 1000 Hz. The changes in frequency produced by a 1‐ Hz change in set frequency were calculated. Actual and displayed frequencies were compared. Results: For settings up to 12 Hz, median (range) difference between set and delivered frequencies was 0 (?0.4 to +0.1) Hz. Above 12 Hz, delivered frequency varied by ?0.3 (?1.9 to +0.3) Hz. For 1‐ Hz changes in frequency settings, in the range 5–12 Hz, 1‐ Hz changes produced a change in delivered frequency of 1.0 (0.6–1.4) Hz. Above 12 Hz, the corresponding changes were 0.7 (0–2.9) Hz. The ventilator displays the set frequency during operation rather than the delivered frequency. Conclusion: At 12 Hz and below, the differences between set and delivered frequencies were relatively small compared with those at 13 Hz and higher. Above 13 Hz, the difference between set and delivered frequencies was up to 2.9 Hz. Some frequency setting changes did not result in a change in delivered frequency. 相似文献
33.
Masquelier B Costagliola D Schmuck A Cottalorda J Schneider V Izopet J Calvez V Descamps D Poggi C Brun-Vézinet F;ANRS resistance sudy group 《Journal of medical virology》2005,76(4):441-446
The objective of the study was to estimate the prevalence of HIV-1 resistance to all drugs belonging to two or more antiretroviral drug (ARV) classes in treated patients in France. All genotyping assays performed in June 2001 and in November 2002 by the ANRS resistance laboratory network were analyzed by the ANRS algorithm. The 17 and 21 centers of the ANRS network participating in the study in 2001 and 2002, respectively, genotyped the viruses in plasma of 456 and 529 patients, respectively. In 2002, the proportions of patients harboring viruses fully resistant to one, two, and three ARV classes were 5.1%, 8.1%, and 2.5%, respectively. These results were similar to those obtained in 2001. In 2002, among the 56 patients with viruses completely resistant to at least two ARV classes, 98%, 96%, and 29% of patients had viruses with complete class resistance to NRTIs, NNRTIs, and PIs, respectively. Complete resistance to PIs was less frequent than full resistance to the other two ARV classes, and ritonavir-boosted amprenavir and lopinavir/r remained potentially active in respectively 71.4% and 42.9% of these 56 patients. In 2001 and 2002, respectively 30% of the 65 patients and 24% of the 56 patients with viruses completely resistant to at least two ARV classes were at an advanced stage of HIV disease, with CD4(+) cell counts below 200/microl and viral loads above 30 000 copies/ml. In France, the prevalence of HIV-1 viruses completely resistant to two or more ARV classes remained stable between 2001 and 2002. Resistance to RT inhibitors was more frequent than resistance to PIs in patients with viruses completely resistant to two or three classes of ARV. 相似文献
34.
Human natural killer (NK) cells are effectors of innate immunity, capable of killing transformed or virus-infected cells and producing pro-inflammatory cytokines. Soluble molecules of HLA-I (sHLA-I), which are significantly increased in the serum of patients affected by auto-immune or infectious or neoplastic diseases, induce NK cell apoptosis interacting with its ligands, such as CD8 or the activating isoforms of members of inhibitory superfamily receptors (IRS). This cell death is accompanied by the release of large amounts of interferon-gamma. NK cells can kill autologous target cells, including antigen presenting cells or infected or tumor cells, by engaging the natural cytotoxicity receptors (NCR) NKp30, or NKp44 and NKp46. Again, the binding between NCR on NK cells and their putative ligands on targets leads to NK cell apoptosis. FasL produced and secreted by NK cells is responsible for the NK cell apoptosis induced by either HLA-I receptors or NCR. Interestingly, cyclosporin A (CsA) blocks NK cell death consequent to interaction with target cells or with sHLA-I, without affecting the activation of cytolysis. This would indicate that CsA can maintain NK cell-dependent innate immunity by prolonging NK cell survival in an hostile environment in the presence of sHLA-I or target cells. 相似文献
35.
PG Kareru JM Keriko GM Kenji GT Thiong'o AN Gachanja HN Mukiira 《African journal of traditional, complementary, and alternative medicines》2010,7(3):214-218
In this study, Tithonia diversifolia Helms. (A Gray), Aloe secundiflora (Miller) and Azadirachta indica (A. Juss) plant extracts were used to make herbal soaps while Thevetia peruviana (Schum) seed oil was used to make a herbal lotion for skincare. The soaps were tested for the growth inhibition of Escherichia coli, and Candida albicans. The lotion was evaluated against Staphylococcus aureus and E.coli. Although Tithonia diversifolia soap exhibited the highest inhibitory effect on the test bacterial strains, it had the least inhibition against C. albicans. Results from this study indicated that the ‘Tithonia diversifolia’ soap would have superior skin protection against the tested bacteria but would offer the least skin protection against C. albicans. The herbal lotion inhibited S. aureus and E. coli in a concentration dependent manner, however, the inhibitory effect was more pronounced on S. aureus. 相似文献
36.
R. A. Sinico N. Mezzina B. Trezzi GM. Ghiggeri A. Radice 《Clinical and experimental immunology》2016,183(2):157-165
Membranous nephropathy (MN), the leading cause of nephrotic syndrome in adults, is characterized by the deposition of subepithelial immune deposits that consist mainly of immunoglobulin (Ig)G and complement. Most of the cases are primary or idiopathic (iMN), while only approximately 25% of the cases are secondary to some known disease such as systemic lupus erythematosus, hepatitis B, drugs and malignancies. Most of our knowledge on the pathogenesis of iMN has relied upon old experimental models (i.e. Heymann nephritis) that have shown that immune deposits are formed in situ by the reaction of autoantibodies against the respective podocyte antigen. Recent findings indicate that podocyte proteins also act as an autoantigen in human iMN. The M‐type phospholipase A2 receptor (PLA2R) has been identified as the main target antigen, as it can be found in approximately 70% of iMN patients but only rarely in other glomerulonephritides. Podocytes damage in the experimental model of Heymann nephritis is complement‐mediated. In humans, the presence of complement within the subepithelial deposits is well established, but IgG4, which does not activate complement by classical or alternative pathways, represents the predominant subclass of IgG anti‐PLA2R. Some evidence suggests that IgG4 anti‐PLA2R autoantibodies can bind mannan‐binding lectin (MBL) and activate the lectin complement pathway. A genetic background for iMN has been demonstrated by genome‐wide association studies that have shown highly significant associations of the PLA2R1 and the human leucocyte antigen (HLA)‐DQA1 loci with iMN. In addition to their diagnostic value, anti‐PLA2R antibodies may be useful to monitor disease activity and predict response to treatment. 相似文献
37.
Human gammadelta T cells: a nonredundant system in the immune-surveillance against cancer. 总被引:4,自引:0,他引:4
Marina Ferrarini Elisabetta Ferrero Lorenzo Dagna Alessandro Poggi Maria Raffaella Zocchi 《Trends in immunology》2002,23(1):14-18
Down-regulation of expression of MHC alleles, as well as tumor-specific antigens, is observed frequently during tumor progression, resulting in an impairment of MHC-restricted, alphabeta-T-cell-mediated, tumor-specific immunity. Given the unique set of antigens recognized and the lack of requirement for classical antigen-presenting molecules, gammadelta T cells might, therefore, represent a nonredundant system in anticancer surveillance, as proposed for the immune response against pathogens. Evidence that gammadelta and alphabeta T cells make distinct contributions to anticancer surveillance has been provided recently in mice. Here, we discuss the potential role played by resident Vdelta1(+) and circulating Vdelta2(+) T cells in the defense against solid tumors and hematological malignancies. 相似文献
38.
Alain?LafeuilladeEmail author Assi?Assi Cécile?Poggi Caroline?Bresson-Cuquemelle Eric?Jullian Catherine?Tamalet 《AIDS research and therapy》2014,11(1):33
Background
Ongoing HIV-1 replication in lymphoid cells is one explanation of the persistence of HIV-1 reservoirs despite highly active antiretroviral therapy (cART). We tested the potential of cART intensification by Maraviroc plus Raltegravir to decrease proviral HIV-1 DNA levels in lymphoid cells during a randomized trial.Patients and methods
We randomly assigned for 48 weeks 22 patients to continue their current first line regimen of Truvada® plus Kaletra® or intensify it with Maraviroc and Raltegravir. The primary objective was to obtain a 50% decrease in proviral HIV-1 DNA levels in lymphoid cells with intensification. Blood samples were drawn at W-2, W0, W2, W4, W12, W24 and W48. Plasma viremia, cellular proviral DNA and cellular RNA, 2-LTR circles and lymphocytes subsets were assayed using validated methods. Patients in the intensified group underwent a gut biopsy at baseline and W48 to measure proviral DNA levels. Statistical analysis used parametric and non-parametric tests.Results
Ten patients in each arm completed the trial. The 2 populations were comparable at baseline. No change in the reservoir size was observed in the intensified arm compared to the control arm measured in peripheral blood mononuclear cells (PBMCs). No change in the reservoir size was observed in gut proviral DNA in the intensified arm. In this group, no increase in 2-LTR circles was observed as early as 2 weeks after intensification and no change was found in residual plasma RNA levels measured by the single copy assay. However, a decrease in CD8+ T cells activation was observed at 24 and 48 weeks, as well as in PBMCs HIV-1 RNA levels.Conclusion
We conclude that the intensification of a Protease Inhibitor regimen with Maraviroc and Raltegravir does not impact the blood proviral DNA reservoir of HIV but can decrease the cell-associated HIV RNA, the CD8 activation and has a possible impact on rectal proviral HIV DNA in some patients.Trial registration
ClinicalTrials.gov identifier number NCT0093548039.
Janneke AL van Kempen Henk J Schers Anne Jacobs Sytse U Zuidema Franca Ruikes Sarah HM Robben René JF Melis Marcel GM Olde Rikkert 《The British journal of general practice》2013,63(608):e225-e231
Background
Primary care is increasingly interested in the identification of frailty, as it selects the target population for integrated care. However, instruments for the identification of frailty specifically validated for use in primary care are scarce. This study developed the Easycare Two-step Older persons Screening (Easycare-TOS), which provides a valid, efficient, and pragmatic screening procedure to identify frail older people.Aim
This paper aims to describe the development of the Easycare-TOS and the data from the pilot studies.Design and setting
Observational pilot study in seven academic GP practices in and around Nijmegen, The Netherlands.Method
The Easycare-TOS was developed in a cyclic process with the input of stakeholders. In every cycle, the requirements were first defined, then translated into a prototype that was tested in a pilot study. The Easycare-TOS makes optimal use of prior knowledge of the GP, and the professionals’ appraisal is decisive in the frailty decision, instead of a cut-off score. Further, it considers aspects of frailty, as well as aspects of the care context of the patient.Results
The pilot data have shown that after step 1, two-thirds of the patients do not need further assessment, because they are judged as not frail, based on prior knowledge of the GP. The overall prevalence of frailty in this pilot study is 24%. Most professionals who participated in the pilot studies considered the time investment acceptable and the method to be of added value.Conclusion
The Easycare-TOS instrument meets the predefined efficiency, flexibility, and acceptability requirements for use as an identification instrument for frailty in primary care. 相似文献40.
Early transvaginal ultrasound following an accurately dated pregnancy: the importance of finding a yolk sac or fetal heart motion 总被引:1,自引:2,他引:1
Deaton JL; Honore GM; Huffman CS; Bauguess P 《Human reproduction (Oxford, England)》1997,12(12):2820-2823
Our goals were to determine the prognostic value of a yolk sac or fetal
heart motion seen during an early accurately dated transvaginal ultrasound
(TVU). We reviewed 225 consecutive pregnancies for fetal heart motion data.
Furthermore, 63 pregnancies following in-vitro fertilization were reviewed
for yolk sac information. The TVU was performed between 5 and 6 weeks
following presumed conception (heart motion data) and between 22 and 32
days following in-vitro fertilization (yolk sac data). Pregnancies were
followed until an ongoing pregnancy or spontaneous abortion was documented.
The presence of a yolk sac between 22 and 32 days from fertilization was
associated with the development of fetal heart motion in 94% of cases. The
absence of the yolk sac by 32 days after fertilization was always
associated with a poor outcome. In women < 36 years of age, the presence
of fetal heart motion was associated with a spontaneous abortion in only
4.5% of the cases. However, the incidence of spontaneous abortion following
fetal heart motion increased to 10% in women 36-39 years and 29% in women
> or = 40 years of age. The presence of heart motion should not be
considered a reassuring sign in the older woman. These data have
implications regarding early embryology and the counselling of infertility
patients.
相似文献